Earlier this month, Kirobo, the world's first talking robot astronaut and Japan's gift to the International Space Station, said some of his first words. Now, Robonaut, who has been on the space station for two and a half years, is about to go on a walkabout.

NASA will launch legs for Robonaut on the next SpaceX mission. The legs will allow him to move through the space station using toe-like fixtures to latch on for chores. Right now, his torso, head and arms are anchored to a platform, which means astronauts have to bring tasks to him.

Rob Ambrose, who heads the robotics program at the Johnson Space Center in Houston, said a mobile Robonaut makes him more useful as a crew member on the space station, allowing him to take over some of the tedious maintenance tasks.

"If I ask anyone I am with, 'What would you like a robot to do?' Kids always say two things: 'My homework' and 'Clean my room,'" Ambrose told ABC News. "Adults usually mention 'Clean the kitchen or the bathroom.'"

Astronauts on the space station spend a lot of time cleaning and keeping up their home above Earth. Yes, the toilet in particular takes a lot of maintenance.
Ambrose said he has gotten a long list from the astronauts about what they want an robot to do for them.

"Some of their tasks are just boring -- holding a sensor in front of an air filter and move it over after about five minutes. Then repeat," he explained.

But others see some different tasks for these humanoids. Former astronaut Steve Hawley, a professor of astronomy at the University of Kansas and a veteran of five Space Shuttle flights, including two Hubble Space Telescope missions, envisions robots taking over some tasks that are just too dangerous for humans.

"There are places on the space station no camera can see -- if you send a robot out to circle around the space station and transmit video, that would give you quick answers to how it's operating -- and be able to check for damage," Hawley told ABC News.

"The robots on Mars are probably there forever. But that's okay for a robot."

Humans and robots make a good team in space, Hawley said. "If we go to Mars, you could send the robot out for long distances to bring samples back to an astronaut at a habitat."

That is the key, according to Ambrose: You can launch a robot, send it outside, and it doesn't need food, or water or a return ticket.

"Those robots on Mars are not going to come home the easy way, and they get one-way tickets. The robots on Mars are probably there forever. But that's okay for a robot," Ambrose said.

That's why Ambrose anticipates robots could work as an advance team for an eventual human mission to Mars. "We could deploy the habitat years in advance with a robot to putter around and set things up to be ready for a human crew," Ambrose said.

Big Personalities

But these robots aren't just robots. NASA has been working hard to give them personalities. Remember HAL in the movie "2001: A Space Odyssey"?

"Dave: Open the pod bay doors, HAL. HAL: I'm sorry, Dave. I'm afraid I can't do that. Dave: What's the problem? HAL: I think you know what the problem is just as well as I do."

But, real-life robots are much less threatening. Robonaut and Kirobo give off a much more relaxed vibe, at least on Twitter. These two robots are so friendly you could imagine C3PO playing Robonaut in the movies, and R2D2 could almost pass for Kirobo.

Kirobo is the first space robot that can talk and react to an astronaut -- his voice and face-recognition software are top secret -- so confidential that when we asked Japanese Astronaut Koichi Wakata about him, Wakata demurred, on the grounds that it was propriety information. Kirobo is probably the cutest robot to go to space, which is good, since his job is be Wakata' s companion on the space station when he takes over command.

Robonaut is more the strong silent type.

Robonaut is more the strong silent type. He isn't chatty, but his tweets show a sense of humor -- telling Mars Curiosity he wasn't into long-distance relationships and mentioning he would take up the guitar since there were no pianos on the space station.

Ambrose said he hopes robots of the future won't be a smarty pants like Star Trek's Commander Data. "The first science fiction movie I really remember was 'Silent Running,'" he said. "It was about a set of robots that helped tend gardens in space and they had a little personality -- Huey and Dewey."